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1.
Animal ; 17(11): 100898, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37558583

RESUMO

Increased ruminal butyrate production is considered to have a positive impact on rumen epithelium growth and function. However, excessive ruminal butyrate production may affect the rumen negatively, particularly when the rumen is already challenged with low pH. The aim of this study was to determine the effect of the inclusion of concentrates in the diet and sodium butyrate (SB) supplementation on ruminal epithelium growth and function in growing rams. Forty-two rams (27.8 ± 7.3 kg; 9-14 months of age) were allocated into six treatments and fed a diet with low (22.5% of diet DM; LOW) or high (60% of diet DM; HIGH) inclusion of concentrates in combination with no (SB0), 1.6% (SB1.6) or 3.2% (SB3.2) of diet DM inclusion of SB. There was no impact of the investigated factors on papilla dimensions and mucosa surface area, either in the atrium ruminis or ventral rumen (P ≥ 0.11). Stratum corneum thickness was higher for HIGH compared to LOW treatments (P ≤ 0.04), independently of the location in the rumen. In the atrium ruminis, the epithelium and living strata thickness quadratically increased due to SB supplementation for LOW treatments but quadratically decreased for HIGH treatments (concentrate inclusion × butyrate supplementation interaction; P ≤ 0.03); conversely, in the ventral sac of the rumen, a thicker epithelium was observed due to both increased concentrate inclusion in the diet and SB supplementation (P < 0.01) but living strata thickness was increased only by SB supplementation (linear effect; P < 0.01). The epithelium damage index in the ventral sac of the rumen was higher for LOW compared to HIGH treatments (P = 0.02). Increased inclusion of concentrates in the diet increased mRNA expression of monocarboxylate transporter 1 in both the epithelium of the atrium ruminis and ventral rumen, occludin in the epithelium of the atrium ruminis and downregulated in adenoma in the epithelium of the ventral rumen (P ≤ 0.02). Protein expression of claudin-4 in the epithelium of the ventral rumen was the highest for the HIGH/SB1.6 and HIGH/SB3.2 treatments (significant effect of interaction between main effects; P < 0.01). Under the conditions of the current study, increased intake of concentrates had mostly positive effects on ruminal epithelium in growing rams, and the same was observed for the effect of SB supplementation. However, the effect of SB supplementation was at least partially affected by the inclusion of concentrates in the diet.


Assuntos
Ração Animal , Rúmen , Ovinos , Animais , Masculino , Ácido Butírico , Rúmen/metabolismo , Ração Animal/análise , Epitélio/metabolismo , Carneiro Doméstico , Dieta/veterinária , Suplementos Nutricionais , Fermentação , Ácidos Graxos Voláteis/metabolismo
2.
Animal ; 17(11): 100899, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37558584

RESUMO

Increased ruminal butyrate production is considered to have mostly positive impacts on rumen macro- and microanatomy and its functions. However, excessive ruminal butyrate production may also affect the rumen negatively. Forty-two growing rams were allocated into six treatments and fed a diet with low (22.5% of diet DM; LOW) or high (60% of diet DM; HIGH) inclusion of concentrates in combination with no, low (1.6% of diet DM) or high (3.2% of diet DM) sodium butyrate (SB) supplementation to obtain low or high reticuloruminal (RR) pH with different concentrations of butyrate. Both absolute (L/day) and relative (% of BW) water intake increased linearly with increasing dose of SB (P ≤ 0.02). The RR fluid pH was lower for HIGH compared to LOW treatments (P < 0.01) but was not affected by SB supplementation (P = 0.35). Total short-chain fatty acid concentration, propionate and valerate concentrations in the RR fluid were higher for HIGH compared to LOW treatments (P ≤ 0.01), but were not affected by SB supplementation (P ≥ 0.22). Reticuloruminal butyrate was higher for HIGH compared to LOW treatments and increased linearly with increasing dose of SB (P < 0.01). High concentrate inclusion in the diet (P < 0.01) decreased and SB supplementation tended to (P = 0.10) decrease fibrolytic activity in the RR. Increasing doses of SB linearly decreased acetate, isovalerate and NH3-N concentrations in RR fluid, and RR digesta DM weight (g DM/kg BW; P ≤ 0.02). Relative RR and rumen tissue weights (g/kg BW) were higher for LOW compared to HIGH (P ≤ 0.03) treatments but were not affected by SB inclusion in the diet (P ≥ 0.35). Also, there was no impact of concentrates or SB inclusion in the diet on ruminal epithelium DM weight (mg/cm2), either in the ventral or dorsal sac of the rumen (P ≥ 0.14). Under conditions of the current study, SB supplementation in the diet decreased RR digesta DM concentration and weight, acetate, isovalerate and NH3-N concentration in the RR fluid, and tended to reduce fibrolytic activity in the RR. At least part of this response could be due to increased intake of water, and consequently passage of digesta from the RR to lower regions of the gastrointestinal tract.


Assuntos
Ração Animal , Ácidos Graxos Voláteis , Ovinos , Animais , Masculino , Ácido Butírico/metabolismo , Fermentação , Ração Animal/análise , Ácidos Graxos Voláteis/metabolismo , Dieta/veterinária , Acetatos/farmacologia , Carneiro Doméstico , Suplementos Nutricionais , Rúmen/metabolismo , Digestão
3.
J Dairy Sci ; 104(6): 6663-6676, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33685670

RESUMO

The aim of this study was to assess the effect of protein source, either soybean meal (SM) or canola meal (CM), and microencapsulated sodium butyrate (MSB) supplementation in a pelleted starter mixture on the development of the gastrointestinal tract (GIT) in dairy calves. Twenty-eight bull calves (8.7 ± 0.8 d of age and 43.0 ± 4.4 kg; mean ± SD) were assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement: CM as a main source of protein without or with MSB or SM without or with MSB. Calves were fed starters ad libitum and exposed to a gradual weaning program, with weaning taking place on 51.7 ± 0.8 d of age. Calves were observed for an additional 3 wk after weaning and slaughtered on d 72.1 ± 0.9 of age, after which the GIT was dissected. Morphometric measurements were recorded, and samples for determination of ruminal fermentation, histology, gene expression, and brush border enzyme activities were collected. Canola meal use in the starter mixture increased abomasal tissue weight, jejunal tissue weight and length, and mRNA expression of SLC16A4 (formerly known as MCT4) and FFAR2 (GPR43) in the ruminal epithelium, and decreased ruminal ammonia and mRNA expression of SLC15A2 (PEPT2) and SLC6A14 (ATB0+) in the proximal small intestine and ileum, respectively. However, MSB inclusion in the starter mixture decreased ruminal papillae length, ruminal epithelial surface, and ruminal epithelium dry weight, while increasing mRNA expression of SLC16A1 (MCT1) in ruminal epithelia. Reduced ruminal surface area associated with MSB supplementation was the most apparent when MSB was combined with CM in the starter mixture. Additionally, MSB supplementation decreased the thickness of omasal epithelium, omasal epithelium living strata, and stratum corneum, and increased duodenal and ileal aminopeptidase A enzymatic activity and ileal aminopeptidase N enzymatic activity. Overall, CM might increase growth of the GIT of calves, particularly of the small intestine, but may negatively affect intestinal epithelium function and peptide and AA absorption. Supplementation of MSB has a negative effect on the ruminal and omasal epithelium development, particularly when combined in a starter mixture with CM.


Assuntos
Ração Animal , Rúmen , Ração Animal/análise , Animais , Ácido Butírico , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Trato Gastrointestinal , Masculino , Glycine max , Desmame
6.
J Biomed Mater Res A ; 105(6): 1607-1617, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28002653

RESUMO

Three medically used alloys (Ti6Al4V, Ti6Al7Nb, and AISI 316 L) are compared due to proliferative potential and metabolic response of human cells (osteoblasts line Saos-2 and endothelial cells line EA.hy-926) seeded on the surfaces of these alloys. Although no statistically significant difference in the proliferative potential of the cells cultured on the surfaces of examined biomaterials was observed, it does not exclude relevant differences in metabolic response of these cells assessed as changes in genes' expression. As a result of our studies it was demonstrated that the changes in the expression of examined genes were very common. Our observation suggests the presence of the process of selective recognition of the contacted biomaterials by the cells seeded on their surfaces. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1607-1617, 2017.


Assuntos
Materiais Biocompatíveis/química , Células Endoteliais/metabolismo , Genes cdc , Osteoblastos/metabolismo , Titânio/química , Ligas , Técnicas de Cultura de Células , Linhagem Celular , Proliferação de Células , Células Cultivadas , Células Endoteliais/citologia , Regulação da Expressão Gênica , Humanos , Osteoblastos/citologia
7.
Chem Phys Lipids ; 178: 38-44, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316311

RESUMO

Lipid bilayer properties are quantified with a variety of arbitrary selected parameters such as molecular packing and dynamics, electrostatic potentials or permeability. In the paper we determined the effect of phloretin and 6-ketocholestanol (dipole potential modifying agents) on the membrane hydration and efficiency of the trans-membrane water flow. The dynamics of water molecules within the lipid bilayer interface was evaluated using solvent relaxation method, whereas the osmotically induced trans-membrane water flux was estimated with the stopped-flow method using the liposome shrinkage kinetics. The presence of phloretin or 6-ketocholestanol resulted in a change of both, the interfacial hydration level and osmotically driven water fluxes. Specifically, the presence of 6-ketocholestanol reduced the amount and mobility of water in the membrane interface. It also slows the osmotically induced water flow. The interfacial hydration change caused by phloretin was much smaller and the effect on osmotically induced water flow was opposite to that of 6-ketocholestanol.


Assuntos
Cetocolesteróis/química , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Floretina/química , Corantes Fluorescentes/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Permeabilidade , Água/química
9.
J Biomed Mater Res A ; 100(3): 768-75, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22238248

RESUMO

Titanium alloys are still on the top list of fundamental materials intended for dental, orthopedics, neurological, and cardiovascular implantations. Recently, a special attention has been paid to vanadium-free titanium alloy, Ti6Al7Nb, that seems to represent higher biocompatibility than traditional Ti6Al4V alloy. Surprisingly, these data are not thoroughly elaborated in the literature; particularly there is a lack of comparative experiments conducted simultaneously and at the same conditions. Our study fills these shortcomings in the field of blood contact and microbiological colonization. To observe platelets adhesion and biofilm formation on the surfaces of compared titanium alloys, fluorescence microscope Olympus GX71 and scanning electron microscope HITACHI S-3000N were used. Additionally, flow cytometry analysis of platelets aggregation and activation in the whole blood after contact with sample surface, as an essential tool for biomaterial thrombocompatibility assessment, was proposed. As a result of our study it was demonstrated that polished surfaces of Ti6Al7Nb and Ti6Al4V alloys after contact with whole citrated blood and E. coli bacterial cells exhibit a considerable difference. Overall, it was established that Ti6Al4V has distinct tendency to higher thrombogenicity, more excessive bacterial biofilm formation and notable cytotoxic properties in comparison to Ti6Al7Nb. However, we suggest these studies should be extended for other types of cells and biological objects.


Assuntos
Materiais Biocompatíveis/química , Biofilmes , Plaquetas/fisiologia , Adesividade Plaquetária/fisiologia , Agregação Plaquetária/fisiologia , Titânio/química , Ligas , Escherichia coli/metabolismo , Humanos , Teste de Materiais , Propriedades de Superfície
10.
Chem Phys Lipids ; 164(4): 276-82, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21376712

RESUMO

In the paper, we present an improved method for evaluation of a compound ability to destabilize erythrocyte plasma membrane. The proposed method is based on the continuous monitoring of the light scattered by erythrocytes exposed to osmotic pressure differences. The kinetics of hemolysis depends on the plasma membrane mechanics and the extent of the osmotic stress. Generally, the osmotic pressure difference of approximately 150 mOsm is taken for measurements, as a result of the equal volume mixing with the physiological salt solutions. In this approach the hemolytic process completion is not established which may result in poor quality and reproducibility of the experimental data. In consequence, inaccurate parameters of the kinetic are determined due to the low quality fitting to the, widely used, single exponential model. In the paper we propose a new experimental protocol allowing to determine the extended set of parameters for kinetics of hemolysis. Namely, the method of the minimal osmotic pressure difference determination is proposed which ensures the completeness of the hemolytic process. This step allows improving the quality and exactness of the calculated parameters. The developed methodology was tested on two qualitatively different, biologically relevant, experiments; evaluation of the peptide effect on the plasma membrane properties and differentiating between human and rabbit erythrocytes.


Assuntos
Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Citometria de Fluxo/métodos , Peptídeos/farmacologia , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Humanos , Cinética , Luz , Pressão Osmótica/efeitos dos fármacos , Peptídeos/química , Quartzo , Coelhos , Valores de Referência
11.
Biochimie ; 88(5): 527-34, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16380202

RESUMO

Cell surface integrins, especially those binding to fibronectin (FN), participate in processes of tumor cell invasion and metastasis. Changes in glycosylation of cell surface adhesion proteins are often associated with malignant transformation of cells. In this study we examined the influence of swainsonine (SW) on adhesion, wound healing and haptotactic migration on FN, comparing the responses of different human melanoma cell lines: primary WM35 and metastatic WM9, WM239 and A375. We also examined the role of alpha subunits in adhesion to FN. All of the antibodies inhibited adhesion to FN but with different efficiencies depending on the cell line. Adhesion was mediated mainly by integrin alpha(5)beta(1) (WM9, A375), alpha(3)beta(1) (WM35, A375, WM239). Scratch wound repair was significantly faster on FN-coated wells than on plastic for all cells except for WM9. A375 and WM9 had the greatest migration ability, both expressing the highest level of alpha(5)beta(1) integrin. It seems very likely that adhesion to FN can be accomplished by many different integrins, but for effective migration alpha(5)beta(1) integrin is responsible. Only A375 and WM239 cell lines reacted to SW treatment. In the presence of SW WM239 and A375 cells had 70% and 40% increased adhesion to FN, and their migration was decreased 40% and 50%, respectively. Interestingly, although most of the cell lines share a common profile of integrins, each line interacted with FN differently. They differed mainly in the repertoire of integrins used for adhesion, and in the manner in which glycosylation affected these processes. The influence of SW was observed in two metastatic cell lines indicating the contribution of glycosylation status to the progression of melanoma. The lack of reaction to SW in WM9 cells may suggest that there is a threshold in the expression level of the highly branched N-glycans that may influence the adhesion and migration properties of the cell.


Assuntos
Fibronectinas/metabolismo , Melanoma/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Glicosilação/efeitos dos fármacos , Humanos , Integrinas/metabolismo , Melanoma/patologia , Ligação Proteica/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Swainsonina/farmacologia
12.
Biochimie ; 87(2): 133-42, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15760705

RESUMO

In tumour cells, alterations in cellular glycosylation may play a key role in their metastatic behaviour. This study used cell lines having very different behaviour in vivo: HCV29 non-malignant transitional epithelium and T24 bladder transitional cell carcinoma. These differences in behaviour might be due in part to differences in cellular glycosylation patterns. Glycan chain analysis of their glycoproteins was performed with the use of specific lectins. The functional role of carbohydrates was studied by treating these cells with swainsonine, an inhibitor of Golgi alpha-mannosidase II, and in vitro adhesion and migration assays. The adhesion of swainsonine-treated HCV29 and T24 cells was increased on fibronectin and type IV collagen by 1.5- and 2-fold, respectively, whereas adhesion on laminin was virtually unchanged after swainsonine-treatment in HCV29 cells and was increased in T24 cells. Swainsonine treatment reduced the rate of T24 cell migration by 20%. We concluded that beta1-6 branched tri- and tetraantennary complex-type glycans have an important function in adhesion and migration in the studied cell lines. These data support the view that oligosaccharides are involved in several steps of the metastatic process.


Assuntos
Movimento Celular , Células Epiteliais/metabolismo , Polissacarídeos/biossíntese , Ureter/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Células Epiteliais/química , Feminino , Glicosilação/efeitos dos fármacos , Humanos , Masculino , Polissacarídeos/química , Especificidade da Espécie , Swainsonina/farmacologia , Ureter/química , Ureter/citologia , Neoplasias da Bexiga Urinária/química , Neoplasias da Bexiga Urinária/patologia
13.
Physiol Res ; 53(3): 317-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15209540

RESUMO

The total protein glycosylation profile and specific activity of lysosomal enzymes were investigated in rat submandibular glands isolated from very young (1-month), young (1.5-months) and adult rats (3-months) rats. The specific activity of lysosomal hydrolases (i.e. acid phosphatase, arylsulfatases A and B, beta-N-acetyl-D-glucosaminidase, beta-galactosidase and beta-glucuronidase) decreased in parallel to increasing age of the animals. Furthermore, the thermal stability of acid phosphatase and beta-N-acetyl-D-glucosaminidase was influenced by the age of rats. Age-related changes in protein profile regarding the intensity of particular bands as well as the appearance of certain proteins limited to special age groups were also demonstrated as revealed by Coomassie and lectin staining. Moreover, the marked age-related increase in structures Man (alpha1-2, alpha1-3, alpha1-6) Man, Fuc (alpha1-6) GlcNAc as well as Gal (beta1-3) GlcNAc was observed, whereas staining with terminal NeuAc and GlcNAc showed an inverse correlation. The reaction with (beta1-6) branched N-glycans and Gal (beta1-3) Gal structures was limited to 1-month-old rats. No significant changes in a specific reaction with NeuAc (alpha2-3) Gal were observed. We speculate that the observed differences with respect to protein and glycosylation profiles between 1-month-old rats and older ones could be caused by a modification of the diet composition as well as by the functional and morphological maturation of the rat submandibular gland.


Assuntos
Envelhecimento/fisiologia , Glicosídeo Hidrolases/metabolismo , Lectinas/metabolismo , Oligossacarídeos/metabolismo , Glândula Submandibular/fisiologia , Fatores Etários , Animais , Ativação Enzimática/fisiologia , Glicosilação , Hidrolases , Lisossomos/fisiologia , Masculino , Ligação Proteica , Ratos , Ratos Wistar
14.
Melanoma Res ; 11(3): 205-12, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11468508

RESUMO

Glycosylation is generally altered in tumour cells in comparison with their normal counterparts. These alterations are thought to be important because they contribute to the abnormal behaviour of cancer cells. Therefore, we have comparatively analysed the glycoproteins in cell extracts from human melanoma (primary site--WM35; metastatic sites-- WM239, WM9 and A375) cell lines using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and lectin staining. The glycoprotein pattern of the WM35 line differed from that of the other cell lines in having less proteins that reacted with Sambucus nigra, Maackia amurensis and Phaseolus vulgaris agglutinins. A glycoprotein of about 70 kDa had a significantly increased reaction with Sambucus nigra agglutinin in all the cell lines from metastatic sites. In the WM9, WM239 and A375 cell lines, additional bands (160-100 kDa) were stained with Phaseolus vulgaris agglutinin, suggesting that cells from metastatic sites contain more glycoproteins with beta1-6 branches. On the other hand, only minor changes in the reaction with Galanthus nivalis agglutinin, a mannose-specific lectin, were detected. Among the proteins showing different lectin staining, one, with an apparent molecular weight of 133 kDa, was recognized by antibodies as N-cadherin. The present results suggest that in human melanoma the expression of branched and sialylated complex type N-oligosaccharides consistently increased in cells from metastatic sites, and support the view that carbohydrates are associated with the acquisition of the metastatic potential of tumour cells.


Assuntos
Glicoproteínas/metabolismo , Lectinas/metabolismo , Melanoma/metabolismo , Aglutininas/metabolismo , Western Blotting , Caderinas/biossíntese , Densitometria , Eletroforese em Gel de Poliacrilamida , Galanthus , Glicosilação , Humanos , Fenótipo , Lectinas de Plantas , Ligação Proteica , Células Tumorais Cultivadas
15.
Acta Biochim Pol ; 47(2): 427-34, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11051207

RESUMO

Expression as well as properties of integrins are altered upon transformation. Cell adhesion regulated by integrins is modulated by glycosylation, one of the most frequent biochemical alteration associated with tumorogenesis. Characterisation of carbohydrate moieties of alpha3beta1 integrin on the cultured human bladder carcinoma (T-24, Hu456, HCV 29T) and human normal ureter and bladder epithelium (HCV 29, Hu609) cell lines was carried out after an electrophoresis and blotting, followed by immunochemical identification of alpha3 and beta1 integrin chains and analysis of their carbohydrates moieties using highly specific digoxigenin-labelled lectins. In all the studied cell lines alpha3beta1 integrin was glycosylated although in general each subunit differently. Basic structures recognized in beta1 subunit were tri- or tetraantennary complex type glycans in some cases sialylated (T-24, HCV 29, HCV 29T) and fucosylated (Hu609, HCV 29T). Positive reaction with Phaseolus vulgaris agglutinin and Datura stramonium agglutinin suggesting the presence of beta1-6 branched N-linked oligosaccharides was found in cancerous cell lines (T-24, Hu456) as well as in normal bladder epithelium cells (Hu609). High mannose type glycan was found only in beta1 subunit from Hu456 transitional cell cancer line. On the other hand alpha3 subunit was much less glycosylated except the invasive cancer cell line T-24 where high mannose as well as sialylated tri- or tetraantennary complex type glycans were detected. This observation suggests that changes in glycosylation profile attributed to invasive phenotype are rather associated with alpha3 not beta1 subunit.


Assuntos
Integrinas/química , Antígenos CD/química , Antígenos CD/isolamento & purificação , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Humanos , Integrina alfa3 , Integrina alfa3beta1 , Integrina beta1/química , Integrina beta1/isolamento & purificação , Integrinas/isolamento & purificação , Lectinas , Subunidades Proteicas , Células Tumorais Cultivadas , Ureter , Bexiga Urinária , Neoplasias da Bexiga Urinária , Urotélio
16.
Mech Ageing Dev ; 113(3): 193-203, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10714938

RESUMO

The aim of this study was to determine how glycosylation of the rat liver arylsulfatase B was influenced by the age of the animal. The enzyme was purified from a liver lysosomal fraction obtained from male Wistar rats aged 18 days of gestation, 1 week, and 1, 1.5, 3 and 18 months by an affinity chromatography. Examination of the carbohydrate structures was performed after electrophoresis and blotting, followed by a very sensitive detection system with a set of six highly specific digoxygenin-labelled lectins. After densitometric measurement of the intensity of a digoxigenin-labelled lectin binding to arylsulfatase B, it could be stated that, at least, changes in sialylation are related to the growth and development of rats. Sialylation increases while fucosylation slightly decreases with age of the animal.


Assuntos
Envelhecimento/metabolismo , Fígado/enzimologia , N-Acetilgalactosamina-4-Sulfatase/química , N-Acetilgalactosamina-4-Sulfatase/metabolismo , Animais , Feto/enzimologia , Glicosilação , Lectinas , Fígado/crescimento & desenvolvimento , Lisossomos/enzimologia , Masculino , Ratos , Ratos Wistar
17.
Acta Biochim Pol ; 47(4): 1159-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11996105

RESUMO

Changes in the expression of integrins and cadherins might contribute to the progression, invasion and metastasis of transitional cell cancer of the bladder and of melanomas. The expression of alpha5 (P < 0.001), alpha2 and beta1 (P < 0.05 - P < 0.001) integrin subunits in melanoma cells from noncutaneous metastatic sites (WM9, A375) were significantly increased as compared to cutaneous primary tumor (WM35) and metastatic (WM239) cell lines. These differences might be ascribed to the invasive character of melanoma cells and their metastasis to the noncutaneous locations. The significantly heterogeneous expression of beta1 integrin subunit in two malignant bladder cancer cell lines (T24 and Hu456) and nonsignificant differences in the expression of alpha2, alpha3, and alpha5 subunits between malignant and non-malignant human bladder cell lines do not allow an unanimous conclusion on the role of these intergrin subunits in the progression of transitional cancer of bladder. The adhesion molecule, expressed in all studied melanoma and bladder cell lines, that reacted with anti-Pan cadherin monoclonal antibodies was identified as N-cadherin except in the HCV29 non-malignant ureter cell line. However, neither this nor any other bladder or melanoma cell line expressed E-cadherin. The obtained results imply that the replacement of E-cadherin by N-cadherin accompanied by a simultaneous increase in expression of alpha2, alpha3 and alpha5 integrin subunits clearly indicates an increase of invasiveness of melanoma and, to a lesser extent, of transitional cell cancer of bladder. High expression of N-cadherin and alpha5 integrin subunit seems to be associated with the most invasive melanoma phenotype.


Assuntos
Caderinas/biossíntese , Integrina beta1/biossíntese , Melanoma/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Anticorpos Monoclonais/metabolismo , Western Blotting , Citometria de Fluxo , Humanos , Integrina alfa3beta1 , Integrinas/biossíntese , Metástase Neoplásica , Fenótipo , Testes de Precipitina , Receptores de Colágeno , Receptores de Fibronectina/biossíntese , Células Tumorais Cultivadas
18.
Mech Ageing Dev ; 102(1): 33-43, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-9663790

RESUMO

We studied the pattern of lectins binding by liver lysosomal proteins from rats between 18 days of gestation and 72 weeks of age. An analysis of the carbohydrate structure was carried out after an electrophoresis and blotting, followed by a very sensitive detection system with highly specific digoxigenin-labelled lectins. The only age-related differences were observed in the reaction with sialic acid--(MAA; Macckia amurensis, SNA; Sambucus nigra) and fucose--(AAA; Aleuria aurantia) specific lectins. Sialylation increased and fucosylation decreased with age. We also observed a specific reaction with Galanthus nivalis (GNA), Phaseolus vulgaris (PHA-L) and peanut agglutinin (PNA), without any significant changes with age.


Assuntos
Envelhecimento/metabolismo , Fígado/metabolismo , Proteínas/metabolismo , Animais , Feminino , Feto/metabolismo , Fucose/química , Fucose/metabolismo , Fucosiltransferases/metabolismo , Galanthus , Idade Gestacional , Glicosilação , Lectinas , Fígado/química , Lisossomos/química , Lisossomos/enzimologia , Lisossomos/metabolismo , Masculino , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Lectinas de Plantas , Ratos , Ratos Wistar , Proteínas Inativadoras de Ribossomos , Ácidos Siálicos/química , Ácidos Siálicos/metabolismo , Sialiltransferases/metabolismo , Frações Subcelulares/química , Frações Subcelulares/metabolismo
19.
Acta Biochim Pol ; 45(3): 791-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9918506

RESUMO

Beta-N-acetylhexosaminidase was prepared from a liver lysosomal fraction obtained from rats between 18 days of gestation (group I) and 72 weeks of age (groups II-VI). A glycan chain analysis was performed after an electrophoresis and blotting, followed by a very sensitive detection system with highly specific digoxigenin-labelled lectins. The presence of high-mannose/hybrid type glycans, as well as their fucosylated forms was shown in all the experimental groups. Complex-type glycans with terminal sialic acid or galactose were present in all the groups except for 1-week-old rats in which only a positive reaction with lectins from Galanthus nivalis and Aleuria aurantia was observed. Thus it may be assumed that age-related changes in the glycosylation pattern occur on the first days after birth.


Assuntos
Envelhecimento/metabolismo , Fígado/enzimologia , beta-N-Acetil-Hexosaminidases/metabolismo , Animais , Eletroforese em Gel de Poliacrilamida , Galanthus , Glicosilação , Masculino , Ratos , Ratos Wistar
20.
Acta Biochim Pol ; 44(2): 181-90, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9360706

RESUMO

A glycan chain analysis of the total oligosaccharide pool derived from rat liver arylsulfatase B was carried out by. P4 Gel Permeation Chromatography and sequential exoglycosidase digestion. It was found that 71% of rat liver arylsulfatase B oligosaccharides were sialylated. The relative contribution of particular structures in the total glycan pool was as follows: sialylated biantennary complex type glycans with terminal galactose--65%, high-mannose type glycans--15%, biantennary complex type glycans with core fucose and terminal N-acetylglucosamine--5%, O-linked oligosaccharides--3.5%.


Assuntos
Condro-4-Sulfatase/análise , Fígado/enzimologia , Oligossacarídeos/análise , Animais , Condro-4-Sulfatase/isolamento & purificação , Cromatografia em Papel/métodos , Eletroforese em Gel de Poliacrilamida , Masculino , Oligossacarídeos/isolamento & purificação , Polissacarídeos/análise , Polissacarídeos/isolamento & purificação , Ratos , Ratos Wistar
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